Bridge parts couldn't take the wind

Workers inspect an eyebar support on the Bay Bridge on Wednesday. The bridge remains closed in both directions following a support failure Tuesday evening.

Workers inspect an eyebar support on the Bay Bridge on Wednesday. The bridge remains closed in both directions following a support failure Tuesday evening.

Photo: Noah Berger, Special To The Chronicle

Photo: Noah Berger, Special To The Chronicle

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Workers inspect an eyebar support on the Bay Bridge on Wednesday. The bridge remains closed in both directions following a support failure Tuesday evening.

Workers inspect an eyebar support on the Bay Bridge on Wednesday. The bridge remains closed in both directions following a support failure Tuesday evening.

Photo: Noah Berger, Special To The Chronicle

Bridge parts couldn't take the wind

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High winds caused a steel crossbeam and two steel tie rods to snap off the Bay Bridge's eastern span and fall to the upper deck, Caltrans officials said today as commuters unable to drive over the closed bridge jammed alternative routes and crowded onto BART in record numbers.

The three pieces were part of an emergency repair that workers made on the bridge over the Labor Day weekend after discovering a crack in a structural beam on the cantilever section. The repair held for just seven weeks, until the parts came crashing to the upper deck at 5:30 p.m. Tuesday, damaging three vehicles and injuring one motorist.

Crews worked all night on fresh repairs after authorities closed the bridge and anticipated completing the repairs by noon tomorrow, said Ed Puchi, a spokesman for MCM Construction Inc. of Sacramento, the lead contractor on the project. The National Weather Service said gusts in the San Francisco area hit 30 mph Tuesday. Caltans said that was enough to cause a 20-foot tie rod, which goes through load-bearing steel saddles on the cantilever section, to move back and forth, and eventually snap.

"Basically, it's like taking a paper clip and working it back and forth until it breaks," said Richard Land, Caltrans' chief engineer.

The tie rod was one of four, two on each side, that held the 3-foot-wide steel crossbeam in place. When it snapped, the entire mechanism was suddenly out of balance, and the crossbeam and a second tie rod tore away and fell to the upper deck.

Caltrans officials said they believe they have made an adjustment that will keep the tie rods in place once new repairs are completed. Continuing winds are slowing welding and other work, however.

Many of the 280,000 motorists who drive the span on a typical weekday clogged alternative routes into San Francisco. The San Mateo-Hayward and Richmond-San Rafael bridges were especially bad.

At 8 a.m., the westbound drive across the San Mateo Bridge, which typically takes about 15 minutes, was a 50-minute slog. Overall, traffic on the bridge was about 40 percent heavier than usual, a bridge supervisor said.

Traffic also was heavier on the Golden Gate Bridge, especially in the very early morning. In the 2 a.m. hour, the number of cars was more than triple the average, said Mary Currie, bridge district spokeswoman.

As the morning wore on, the increase dropped dramatically. By the 7 a.m. hour, the number of cars crossing the Golden Gate was only 15 percent above normal, Currie said.

BART spokesman Linton Johnson said the agency brought in extra train operators and added more 10-car trains to cope with the thousands of additional riders flocking to the system. Trains from the East Bay into San Francisco were standing-room only as early as 5:30 a.m., and many station parking lots were full by 7 a.m.

Ridership across the bay was up 47 percent this morning, with 83,000 riders compared with 55,800 on a normal Wednesday, Johnson said. Overall BART ridership was 139,200 this morning, up 24 percent, he said.

BART expects a record number of riders today, Johnson said. "We're in it for the long haul," he said.

Denise Morales, a BART supervisor, surveyed the scene at the 12th Street Station in downtown Oakland and said, "Everybody's pretty complacent. They really understand. They realize what the situation is. They're just grateful they have a way to get into the city."

People also headed for ferries. At Jack London Square in Oakland, the 8:10 a.m. Blue and Gold Ferry to San Francisco had 73 people on it - nine times the typical total.

Doug Brewster was on the 7:40 a.m. crossing. He usually takes AC Transit to his job at Genentech in South San Francisco. That wasn't possible today; AC was picking up riders at transbay-bus stops but delivering them to BART stations.

Brewer opted for the boat. "I think BART is going to be crazy today," he said.

Those who took the AC buses and got off at the West Oakland BART station found that ticket lines were seven people deep.

The repair job that disintegrated on the Bay Bridge Tuesday afternoon had been designed to patch a crack on a steel structural beam, called an eyebar, that was discovered during the Labor Day weekend shutdown of the span. The bridge was closed so workers could install a new, 288-foot S-turn as part of construction of the new eastern span, but the crack was unrelated to that project.

The problem forced officials to push back the announced reopening of the span while emergency repairs were made. Working nearly 70 hours nonstop, crews wrapped a steel brace around the broken beam to redistribute tension away from the damaged area. That brace was then attached to another one set lower on the span using steel rods.

In the end, the bridge reopened in time for most of the morning commute the day after Labor Day.

At the time, Dan Himick, president of the chief contractor on the project, C.C. Myers Inc., declared, "Everything went perfect."

On Tuesday night, Beth Ruyak, a spokesman for C.C. Myers, said the company was committed to helping with the repair.

The firm will be assisting on the job, Caltrans spokesman BART Ney said. .